Internal-combustion engine



Filed April 9. 1928 Patented Aug. 11, 1931 irnanoois FEYENS, or BRUSSELS, BELGIUM, 'ro soorn'rn GENERALE UDES INDUSTBIELLES,

GENERAL RESEARCH CORPORATION, SOCIETE A1\T0- NYME, OF BRUSSELS, BELGIUM, A COMPANY OFBELGIUM INTERlll'AL-COIVIBUSTEON' ENGINE Application filed April 9, 1928, Serial No. 268,541, and in Belgium April 15, 1927.

This invention relates to a device for minimizing or nullitying the disturbing ett'ects upon the working of internal combustion engines, whi ch may be caused by variations of :ressnre oi the surrounding atmosphere, such, as may be metwith by aviation engines operating at different altitudes, this pressure gei'ierally decreasing the higher the altitude reacheiil. To this end the device is designed to oppose to the discharge of the outgoing g eous products of combustion, a counternri sure which can. be varied to suit the ditlerent atmospheric pressures to which the engines are likely to be subjected when operating diiierent altitudes.

The Eoregoing desirable result is attained by discharging the gases from the engine into a chamber whence they reach the atmosnh through a discharge outlet controlled by a valve held to its seat by an adjustable s p r i n The invention is of particular importance when used in connection with certain twostroke engines wherein the volume of air compressed within the engine casings may very largely exceed the capacity of the combustion chambers of said engines, the excess of air beyond that which is required for the charging of the cylinders with the proper explosive mixture being utilized for elliciently scavenging the cylinders, the relative capacities of the casings and the cylinders being designed to secure this result when working with normal external atmospheric pressure. lVhc-n, however, the external pressure is below normal, as at high altitudes or when the exhaust is located in a position in which it is subjected to reduced pressure arisin trom the motion of aircraft on which the is being used, excessive discharge an the exhaust will result in an inetficient ch: oi? the cylinders. The present invent-ion, however, overcomes this difficulty by providing means for establishing a constant counter pressure which will prevent any such eXceF-ssivc discharge.

(his constrlu-tional form of the invention suitable for a six-cylinder engine is diagramn'iatically illustrated in longitudinal section in the accompanying drawin As here shown, the exhaust pipes a all 013m) into a common chamber Z) having a much larger capacity than that of the engine cylinders, that a certaii'i pressure will be produced in the said chamber.

l rom this chan'iber b the gases pass through a relatively restricted pipe or neck of suitable diameter to act as a check on the tree discharge of the into an outlet chamber 0 provided with. a control valve ,1". The re sistance ot' a spring 0 and of the external pressure then overcome by the pressure of the gases within the chamber (Z, and the surplus s are discharged past the valve f. By increasing the tension of the spring 6 to accord with a decrease in the external pressure, it is possible to maintain the counterpressure normal in the exhaust chamber 6, and consequently constant in each cylinder.

The tunction of the outlet 0, which is of restricted area both in relation to the chamber Z) and the outlet chamber (Z, is to cause a check to the discharge of the escaping gases before allowing their expansion into the second cl. Tug chamber (Z, the outlet 0 thus acting as a static checking means, the action of whi h precedes the regulable checking means at the outlet 0f the chamber d, I

Having'described my invention, I declare that what I claim and desire to secure by Letters Patent is l. In combination with an internal combustion engine having an exhaust pipe leading from the engine cylinder, an exhaust chamber connected with said pipe and oi greater capacity than that of the cylinder, an outlet chamber, a neck of reduced crosssectional area connecting the exhaust chamber with the outlet char her and constituting a primary medium for checking the out ii'oiv ot the exhaust gases, an outlet pressure may be cont-rolled to prevent excessive exhaust discharge.

9. In con'ibination with an internal combustion engine having an exhaust pipe leading from the engine cylinder, an exhaust chamber connected with said pipe and of a capacity greater than that of the cylinder, an outlet chamber, a neck of reduced crosssectional area connecting the exhaust chant her with the outlet chamber and constituting a primary medium for checking the outward flow of the exhaust gases, an outlet opening to the atmosphere from the outlet chamberan outwardly opening valve in said outlet operated by the pressure of the outflowing exhaust gases and affording a restricted outlet passage, said valve constituting a secondary medium for checking the flow of the exhaust gases, a spring acting on said valve and tending to close the same, and means for adjusting the tension of the spring: whereby a counter pressure is created which is opposed to the discharge of the exhaust gases, and which counter pressure can be varied to suit diii'ezent atmospheric pressures at diii'erent altitudes.

3. In combination with an internal rombustion engine having a plurality of exhaust pipes leading from a plurality of engine cylinders, an exhaust chamber into which all of said pipes discharge, said chamber having a capacity greater than the combined capacities of all of the cylinders. an outlet chamber, a neck of reduced cross-sectional area connecting the exhaust chamber with the outlet chamber and constituting a primary medium for checking the outward flow of the exhaust gases, an outlet opening to the atmosphere from the outlet chamber, and an outwardly opening valve in said outlet operated by the pressure of the outflowing gases and affording a restricted outlet passage constituting a secondary medium for checking the outward flow of the exhaust gases; whereby a counter pressure is created 0pposed to the discharge of the exhaust gases, which counter pressure may be controlled to prevent excessive exhaust discharge.

i. In combination with an internal combustion engine having a plurality of exhaust pipes leading from a plurality of engine cylinders, an exhaust chamber into which all of said pipes discharge, and having a capacity greater than the combined capacities of all the cylinders, an outlet chamber, a neck of reduced cross sectional area connecting the exhaust chamber with the outlet chamber and constituting a primary medium for checking the outward flow of the exhaust gases, an outlet opening to the atmosphere from the outlet chamber, an outwardly opening valve in said outlet operated by the pressure of the outflowing and. aifording a restricted outlet passage constituting a second medium for checking the flow of the exhaust 

